Chapter 5 The Evolutionary Paths Of Nearby Galaxies
... increasing the stellar mass retained in quiescent systems. In this case, a quenching of the star formation is required to drive galaxies towards the red sequence, but it is still unclear what physical mechanism(s) may be responsible for such migration. The most popular candidate is feedback from the ...
... increasing the stellar mass retained in quiescent systems. In this case, a quenching of the star formation is required to drive galaxies towards the red sequence, but it is still unclear what physical mechanism(s) may be responsible for such migration. The most popular candidate is feedback from the ...
Mapping the Pathways of Galaxy Transformation Across Time and
... activity, stellar mass assembly, and morphology. In this talk, I will illustrate the relation between global properties and kpc-scale substructures of galaxies out to z∼2. Using combined high resolution data from the Hubble Space Telescope and long exposure spectroscopic observations with the Keck t ...
... activity, stellar mass assembly, and morphology. In this talk, I will illustrate the relation between global properties and kpc-scale substructures of galaxies out to z∼2. Using combined high resolution data from the Hubble Space Telescope and long exposure spectroscopic observations with the Keck t ...
X-Ray Properties of Young Stars and Stellar Clusters
... Star and planet formation is generally viewed as a hydrodynamic process involving gravitational collapse of interstellar material at low temperatures, 10–100 K in molecular cloud cores and 100–1500 K in protoplanetary disks. If thermodynamical equilibrium holds, this material should be neutral excep ...
... Star and planet formation is generally viewed as a hydrodynamic process involving gravitational collapse of interstellar material at low temperatures, 10–100 K in molecular cloud cores and 100–1500 K in protoplanetary disks. If thermodynamical equilibrium holds, this material should be neutral excep ...
Towards the Intensity Interferometry Stellar Imaging System
... We envision a two-stage development and implementation of modern SII. In the first stage, SII could be implemented on one or more existing Cherenkov arrays, immediately offering the advantages of blue operation and high resolution. In a second stage, SII could be implemented as an augmentation of a ...
... We envision a two-stage development and implementation of modern SII. In the first stage, SII could be implemented on one or more existing Cherenkov arrays, immediately offering the advantages of blue operation and high resolution. In a second stage, SII could be implemented as an augmentation of a ...
Cool Stars in the Galaxy — A ROSAT and ASCA View.
... This thesis deals mainly with emission from stellar sources, however an understanding of the solar corona is useful when considering the stellar equivalents. Figure 1.1 shows a soft X-ray image of the solar corona obtained using the Japanese Yohkoh satellite. The bright regions are active (emit in t ...
... This thesis deals mainly with emission from stellar sources, however an understanding of the solar corona is useful when considering the stellar equivalents. Figure 1.1 shows a soft X-ray image of the solar corona obtained using the Japanese Yohkoh satellite. The bright regions are active (emit in t ...
SPICA Yellow Book
... of distant galaxies; however, its relatively warm telescope (between 82 and 90 K) greatly limits its sensitivity. A new much more sensitive mission reaching must therefore build on the work started by Herschel and gain a deeper understanding of the physics of the objects discovered there: i.e., to s ...
... of distant galaxies; however, its relatively warm telescope (between 82 and 90 K) greatly limits its sensitivity. A new much more sensitive mission reaching must therefore build on the work started by Herschel and gain a deeper understanding of the physics of the objects discovered there: i.e., to s ...
c Copyright by Jonathan C. McKinney, 2004
... a better scientist. Charles has tirelessly reviewed many of my written works, and with his help, I have gradually improved my skills as a writer. I express a special thanks to Scott Noble and Ruben Krasnopolsky, who both proofread the unpublished parts of my thesis. They gave excellent comments that ...
... a better scientist. Charles has tirelessly reviewed many of my written works, and with his help, I have gradually improved my skills as a writer. I express a special thanks to Scott Noble and Ruben Krasnopolsky, who both proofread the unpublished parts of my thesis. They gave excellent comments that ...
The masses and spins of neutron stars and stellar
... of isolated neutron stars except perhaps by microlensing (and then the identification of the object as a neutron star is not certain). The current spins of pulsars are obviously straightforward to measure, but these spins have been affected strongly by magnetic spindown. However, as we discuss in Se ...
... of isolated neutron stars except perhaps by microlensing (and then the identification of the object as a neutron star is not certain). The current spins of pulsars are obviously straightforward to measure, but these spins have been affected strongly by magnetic spindown. However, as we discuss in Se ...
Studies of molecular clouds at the Galactic centre Roland Karlsson DECLINATION (B1950)
... those may be partly ionised on the surface, we do not consider magnetohydrodynamic effects to be dominant over gravitational and fluid dynamical forces. 1 The ...
... those may be partly ionised on the surface, we do not consider magnetohydrodynamic effects to be dominant over gravitational and fluid dynamical forces. 1 The ...
T3-Cosmic Star Formation History
... The origin and evolution of galaxies are among the most intriguing and complex chapters in the formation of cosmic structure, and observations in this field have accumulated at an astonishing pace. Multiwavelength imaging surveys with the Hubble (HST) and Spitzer space telescopes and ground-based fac ...
... The origin and evolution of galaxies are among the most intriguing and complex chapters in the formation of cosmic structure, and observations in this field have accumulated at an astonishing pace. Multiwavelength imaging surveys with the Hubble (HST) and Spitzer space telescopes and ground-based fac ...
X. Nuclear star clusters in low-mass early-type galaxies
... argument was derived for dissipationless formation): the tidal forces from the SMBH rip inspiralling clusters apart at large radii from the centre, so that the NSC ends up having a much lower density than in the absence of an SMBH and may therefore not be properly disentangled from the host galaxy. ...
... argument was derived for dissipationless formation): the tidal forces from the SMBH rip inspiralling clusters apart at large radii from the centre, so that the NSC ends up having a much lower density than in the absence of an SMBH and may therefore not be properly disentangled from the host galaxy. ...
Markov Chain Monte Carlo Modeling of High-Redshift Quasar
... Balmer series of Hydrogen, with a systematic redshift of z = 0.158, confirming its nature as an extremely luminous extragalactic object. It was found that the dominant optical emission in quasars comes from an extremely compact region located in the nucleus of a host galaxy, with this nuclear emissi ...
... Balmer series of Hydrogen, with a systematic redshift of z = 0.158, confirming its nature as an extremely luminous extragalactic object. It was found that the dominant optical emission in quasars comes from an extremely compact region located in the nucleus of a host galaxy, with this nuclear emissi ...
Dark Matter, Dark Energy, and the Fate of the Universe
... mass is distributed throughout its halo while most of the galaxy’s light comes from stars and gas clouds in the thin galactic disk (see Figure 1.14). We infer the existence of the second unseen influence from careful studies of the expansion of the universe. After Edwin Hubble first discovered the e ...
... mass is distributed throughout its halo while most of the galaxy’s light comes from stars and gas clouds in the thin galactic disk (see Figure 1.14). We infer the existence of the second unseen influence from careful studies of the expansion of the universe. After Edwin Hubble first discovered the e ...
The Collision Between The Milky Way And Andromeda
... is set to match distributions extracted from cosmological Nbody simulations (e.g., Navarro et al. 1996). Together, these models specify the total mass distribution out to the virial radius (∼ 200 − 300 kpc). In our model of the Local Group we start by adopting the models for the Milky Way and Androm ...
... is set to match distributions extracted from cosmological Nbody simulations (e.g., Navarro et al. 1996). Together, these models specify the total mass distribution out to the virial radius (∼ 200 − 300 kpc). In our model of the Local Group we start by adopting the models for the Milky Way and Androm ...
Galaxies
... multi-dimensional distributions of galaxy properties. Tools in use today include the luminosity function of galaxies, the color-luminosity relation, size-luminosity relation, quantitative morphology, and the variation of these distributions with environment (local density or halo mass). As data sets ...
... multi-dimensional distributions of galaxy properties. Tools in use today include the luminosity function of galaxies, the color-luminosity relation, size-luminosity relation, quantitative morphology, and the variation of these distributions with environment (local density or halo mass). As data sets ...
Galaxies - hwchemistry
... of galaxies, however, they find that the measured masses are much larger than expected from the luminosities of the galaxies. • This seems to be true of most galaxies. – Measured masses of galaxies amount to 10 to 100 times more mass than you would expect from the appearance of galaxies. ...
... of galaxies, however, they find that the measured masses are much larger than expected from the luminosities of the galaxies. • This seems to be true of most galaxies. – Measured masses of galaxies amount to 10 to 100 times more mass than you would expect from the appearance of galaxies. ...
book_text4
... The Hubble Space Telescope has undoubtedly had a greater public impact than any other space astronomy mission ever. The images included in this beautiful volume are quite staggering in what they reveal about the Universe we live in and have already become part of our common scientific and cultural h ...
... The Hubble Space Telescope has undoubtedly had a greater public impact than any other space astronomy mission ever. The images included in this beautiful volume are quite staggering in what they reveal about the Universe we live in and have already become part of our common scientific and cultural h ...
A Comet-Hunter`s Legacy -
... causing the fuzzy blurring near its center, and emitting huge amounts of radiation, all the way from the infrared, to the X-ray region. Each hundred-million year passage will probably bring the two galaxies closer together. At first, this will probably produce more and more extreme waves of star for ...
... causing the fuzzy blurring near its center, and emitting huge amounts of radiation, all the way from the infrared, to the X-ray region. Each hundred-million year passage will probably bring the two galaxies closer together. At first, this will probably produce more and more extreme waves of star for ...
ROSAT Ian R. Stevens* and David K. Strickland*
... Contini (1998) lists a further eight EL galaxies with narrow He II l4686. Of these only one, Mrk 49, a blue compact dwarf galaxy (also classified as Mrk 1318), has been observed. However, there seems to be emission from a point source near to but not coincident with Mrk 49 (the X-ray emission is cen ...
... Contini (1998) lists a further eight EL galaxies with narrow He II l4686. Of these only one, Mrk 49, a blue compact dwarf galaxy (also classified as Mrk 1318), has been observed. However, there seems to be emission from a point source near to but not coincident with Mrk 49 (the X-ray emission is cen ...
JENAM-2011 Book of abstracts
... ESA’s Hipparcos astrometry mission was a particularly innovative project in space astronomy. The satellite was launched in 1989 (already more than 20 years ago) with the final Hipparcos and Tycho Catalogues fully published just eight years later. Exceeding the original scientific specifications in term ...
... ESA’s Hipparcos astrometry mission was a particularly innovative project in space astronomy. The satellite was launched in 1989 (already more than 20 years ago) with the final Hipparcos and Tycho Catalogues fully published just eight years later. Exceeding the original scientific specifications in term ...
Evolution in circumstellar envelopes of Be stars: From disks to rings?
... the star and slowly grows outwards. A subsequent outburst may later replenish this cavity. In fact, in two stars this more ring-like structure is apparently at times detached far enough from the star to allow for the formation of a secondary inner disk from the ejecta of a later outburst. This behav ...
... the star and slowly grows outwards. A subsequent outburst may later replenish this cavity. In fact, in two stars this more ring-like structure is apparently at times detached far enough from the star to allow for the formation of a secondary inner disk from the ejecta of a later outburst. This behav ...
Observations of Jets and Outflows from Young Stars
... from the launch region, which can range from 100 to over 500 km s−1 . Internal shocks form where faster ejecta overrun slower material. The very fastest shocks can sometimes be detected in X-rays. These primary flows often contain molecules such as H2 , CO, and SiO when launched from young Class 0/I ...
... from the launch region, which can range from 100 to over 500 km s−1 . Internal shocks form where faster ejecta overrun slower material. The very fastest shocks can sometimes be detected in X-rays. These primary flows often contain molecules such as H2 , CO, and SiO when launched from young Class 0/I ...
Conference Abstract Booklet here.
... and extragalactic fields visited multiple times by the Hubble Space Telescope with the same instrument/filter combination. While some of these fields were searched for specific types of variables before (most notably, the extragalactic Cepheids), we attempt a systematic study of the population of va ...
... and extragalactic fields visited multiple times by the Hubble Space Telescope with the same instrument/filter combination. While some of these fields were searched for specific types of variables before (most notably, the extragalactic Cepheids), we attempt a systematic study of the population of va ...
Gamma-ray burst
Gamma-ray bursts (GRBs) are flashes of gamma rays associated with extremely energetic explosions that have been observed in distant galaxies. They are the brightest electromagnetic events known to occur in the universe. Bursts can last from ten milliseconds to several hours. The initial burst is usually followed by a longer-lived ""afterglow"" emitted at longer wavelengths (X-ray, ultraviolet, optical, infrared, microwave and radio).Most observed GRBs are believed to consist of a narrow beam of intense radiation released during a supernova or hypernova as a rapidly rotating, high-mass star collapses to form a neutron star, quark star, or black hole. A subclass of GRBs (the ""short"" bursts) appear to originate from a different process – this may be due to the merger of binary neutron stars. The cause of the precursor burst observed in some of these short events may be due to the development of a resonance between the crust and core of such stars as a result of the massive tidal forces experienced in the seconds leading up to their collision, causing the entire crust of the star to shatter.The sources of most GRBs are billions of light years away from Earth, implying that the explosions are both extremely energetic (a typical burst releases as much energy in a few seconds as the Sun will in its entire 10-billion-year lifetime) and extremely rare (a few per galaxy per million years). All observed GRBs have originated from outside the Milky Way galaxy, although a related class of phenomena, soft gamma repeater flares, are associated with magnetars within the Milky Way. It has been hypothesized that a gamma-ray burst in the Milky Way, pointing directly towards the Earth, could cause a mass extinction event.GRBs were first detected in 1967 by the Vela satellites, a series of satellites designed to detect covert nuclear weapons tests. Hundreds of theoretical models were proposed to explain these bursts in the years following their discovery, such as collisions between comets and neutron stars. Little information was available to verify these models until the 1997 detection of the first X-ray and optical afterglows and direct measurement of their redshifts using optical spectroscopy, and thus their distances and energy outputs. These discoveries, and subsequent studies of the galaxies and supernovae associated with the bursts, clarified the distance and luminosity of GRBs. These facts definitively placed them in distant galaxies and also connected long GRBs with the explosion of massive stars, the only possible source for the energy outputs observed.